When a connector is plugged into a receptacle, each contact of the connector makes electrical contact with corresponding contacts in the receptacle. This allows electrical signals to pass between the connector and receptacle. Typically, the receptacle uses the same set of contacts each time the connector is plugged in, though in many systems only a subset of the contacts in the set may be used by a given plug or receptacle of a system. Thus, in order for a connector to work with the receptacle, the connector should be designed such that the set of contacts on the connector make contact with the set of contacts on the receptacle. If a connector of a type that has differently configured contact sets is to be plugged into the receptacle, either the connector will not fit into the receptacle, or even if the connector were to fit, the connector contact set would not properly interface with the receptacle contact set. Thus, receptacles have strict limits as to the types of connectors that the receptacle may receive.